The present invention relates generally to ring binders for looseleaf papers and the like, and more particularly to a ring binder constituted of a hollow spine of unitary nature wherein each of the elements thereof are integrally interconnected to one another as a singular unit.
As is well known in the art, there are many ring binders for looseleaf pages which have, or have not, found commercial acceptance in the art. These ring binders are made in many different ways, have operative structure which cooperate with one another in many different ways and are constituted of many different materials such as metal and plastic or the like, each of the conventional ring binders having associated therewith certain advantages and, likewise, certain disadvantages. In this respect, depending on the complexity of the operative association of the various structure with one another, and the specific materials from which the ring binders are manufactured, and the tolerances maintained during the manufacture of the ring binder assembly, the ring binders will operate effectively or uneffectively, reliably or unreliably, and manufactured expensively or inexpensively.
The prior art represents efforts on the part of individuals for developing a ring binder which includes all of the advantages aforementioned in that attempts have been made at developing a ring binder which can be manufactured inexpensively, and will operate with simplicity, yet with reliability.
However, the conventional or prior art variety of ring binders has generally failed to most effectively blend the aforementioned requirements for achieving a most beneficial ring binder design and, therefore, there is somewhat of a void in the art.
In this respect, manufacturers are becoming increasingly aware that the utilization of plastic-like structure will result in an extremely inexpensive ring binder. However, because of the relationship of the structure of the ring binder, the structure being somewhat complex, the ring binder fails to operate in a most effective, reliable and simple fashion.
The conventional type of ring binder which is manufactured of plastic-like material, generally incorporates a plurality of elements which must be mechanically connected to one another, manually or by machine, after the various plastic-like elements have been molded. For example, there are a number of ring binders, of plastic-like nature, which include two separate members and are mechanically connected to one another so as to form the spine of the ring binder. One of the members is constituted as the base of the spine and is provided with generally upstanding sidewalls which terminate respectively in a socket-like elongate free edge. The other member of the spine is generally formed as two elongate segments hingedly associated with one another and integrally interconnected to one another through the intermediary of an elongate scored folding line.
The latter segments are provided with ring halves which are movable toward and away from one another as the latter segments are hingedly movable through the intermediary of the elongate scored folding line. Each of the latter segments is provided with an elongate free edge portion, which is generally rounded, or arcuate in cross-section, the free edge portions being insertable into the elongate edge sockets provided in the base member. This arrangement permits the segments of the second member to be hingedly movable toward and away from the base member about respective axes passing through the elongate sockets in the base member. As the segments of the second member are moved toward the base member, the ring halves carried by these segments are moved into engagement with one another annularly. As the segments of the second member are moved away from the base member, the ring halves are separated from one another in an open or spaced condition.
The disadvantage associated with this variety of prior, or conventional ring binder, rests in the general incapacity for the sockets to retain the arcuate free edge portions of the segments of the second member therein. Because of this incapacity, when the segments are moved away from the base member so as to separate the ring halves from one another, it is possible for the second member to become dislodged from the appropriate sockets therefor, and result in an undesirable disjoinder of the two members from one another, thereby, requiring repair of the spine.
Many attempts have been made in the prior art for overcoming this particular disadvantage such as providing on each of the segments, portions which jut outwardly so as to be hingedly engageable in abutting relation with the exterior of the base member and, thereby, limit the degree to which the segments are movable away from the base segment so as to retain the rounded free edge portions of the segments within the appropriate sockets therefor. Another arrangement for retaining the movable segments and base member in connected relation is the provision of longitudinally opposite ledges which are formed as part of the base member, each ledge provided with a longitudinal finger overlying and spaced from the movable segments and against which the movable segments are engageable for limiting the extent to which the movable segments are displaceable away from the base member.
Another ring binder arrangement for overcoming the aforementioned disadvantages, at least in part, relates to a singular member provided with a plurality of scored folding lines for dividing the element into a base portion and a pair of movable leaves, the leaves constituting the laterally opposite longitudinally extending end portions of the singular member. One leaf is provided with a free edge portion having an elongate socket-like configuration, whereas the other leaf is provided with a transversely rounded elongate edge portion for being generally mechanically interfitted in the socket-like edge portion of the other leaf, each of the leaves carrying respective ring halves for association with one another. The disadvantage associated with this arrangement rests in the tendency for the leaves to become separated from one another at the common joint, namely the interfitted free edges of the leaves respectively and, thereby, in a manner as discussed above for the first mentioned variety of ring binders, require longitudinally opposite abutment ledges for limiting the maximum extent to which the leaves may be moved away from the base portion of the ring binder to prevent the leaves from becoming disjoined from one another.
Clearly, the necessity for providing, as in the prior art, the additional structure for preventing inadvertent separation and disjoinder of the ring binder components from one another, is somewhat of an indication of the problems, heretofore not most effectively solved, when attempting to manufacture ring binders having a plurality of members which require some form of mechanical interconnection to one another.